Apparatus for inserting and ejecting an electronic enclosure within a cabinet

ABSTRACT

A cabinet includes spaces for a number of electronic enclosures, each of which has a free end from which a pair of levers extend upward and downward to teeth engaging slots within the cabinet, aiding in the insertion and removal of the enclosures from the cabinet. An electronic enclosure that is wider than a standard width includes additional teeth on crank plates turning with the levers. The electronic enclosure may include an electrically-operated interlock mechanism preventing the insertion or removal of the electronic enclosure by preventing movement of a shaft attached to either or both of the levers.

CROSS-REFERENCE TO A RELATED APPLICATION

This application is a division of a U.S. patent application Ser. No.10/909,496, which was filed Aug. 02, 2004 now U.S. Pat. No. 7,317,619.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to apparatus for inserting and ejecting anelectronic enclosure within a cabinet, and, more particularly, toproviding forces with such apparatus for the engagement anddisengagement of electrical terminals despite variations in the width ofthe electronic enclosure.

2. Summary of the Background Art

A number of multiple computer installations, such as installations inwhich a number of servers are connected with one another and withcommunications lines, individual computer systems are installed withinindividual electronic enclosures mounted in individual positions, or“slots,” within a cabinet. Such computer systems are configured as“blades” to fit within the cabinet, with each of the individualenclosures being substantially higher than it is wide, and withelectrical connections with the individual systems including an array ofcontact terminals extending from the rear of each individual enclosure.Each such electronic enclosure is inserted into a slot within thecabinet from the front. Since a large number of electrical connectionsare made when the enclosure is fully inserted, an insertion/ejectionmechanism is configured to provide a mechanical advantage helping tomove the enclosure with these terminals to engage contacts within thecabinet, i.e. during an end portion of the process of inserting theenclosure within the slot and during a beginning portion of the processof ejecting the enclosure from the slot.

For example, in the IBM BladeCenter™, each of the electronic enclosuresis provided with an upper lever pivotally mounted on its left side nearits upper front corner and with a lower lever pivotally mounted on theleft side near its lower front corner. The upper lever includes a toothextending upward within a slot in an upper panel extending above theenclosure when the enclosure is fully inserted within the cabinet.Similarly, the lower lever includes a tooth extending downward within aslot in a lower panel extending below the enclosure when the enclosureis fully inserted within the cabinet. Before the electronic enclosurecan be fully inserted within the cabinet, both the upper lever and thelower lever must be pivoted into an open position, with the teeth of thelevers extending inward, out of contact with the upper and lower panels,and with handle portions of the levers extending outward. Then theprocess of inserting the enclosure into the cabinet is completed bypivoting the levers into their closed position, with the teeth of thelevers engaging adjacent edges of the slots in the panels to pull theenclosure inward against the forces developed to establish electricalconnections by engaging contact springs with multiple terminals. Whenthe electronic enclosure is to be removed from the cabinet, thisprocedure is reversed, with the upper and lower levers being pivotedinto the open position so that the teeth of these levers engage edges ofthe slots to eject the enclosure outwardly as the various terminals aredisconnected from the contact springs.

Within the upper and lower panels, the slots are uniformly spaced apartto provide for filling the cabinet with a number of electronicenclosures, each having a common, minimum width. For each of theelectronic enclosures, the upper and lower levers operate, respectively,in a pair of slots that are vertically aligned along the left side ofthe enclosure. While this arrangement is satisfactory for electronicenclosures having the common, minimum width, it does not work well withlarger enclosures having a multiple of the common, minimum width. Sincesuch wider enclosures typically have contact terminal patterns extendingacross a width greater than the common, minimum width, the use of suchan arrangement of levers to install and eject the wider enclosure canresult in difficulties caused by twisting the enclosure along guidesurfaces of the cabinet and contact surfaces during insertion andinjection, with the forces generated by the movement of the lever teethwithin the slots in the upper and lower panels. Thus, what is needed isan insertion and ejection mechanism applying forces at two or morelocations along the width of a wider enclosure.

Furthermore, the width of an individual electronic enclosure can beincreased by adding one or more expansion units, fastened to eitherside, or both sides, of the enclosure. For example, an expansion unitmay include additional hard disk drives to provide increased storagecapacity. Therefore, what is additionally needed is a method for addinga mechanism to apply additional insertion and ejection forces when anexpansion unit is added to an electronic enclosure.

U.S. Pat. App. Pub. Nos. 2003/0101304 and 2003/0030993 describe a bladeserver having an ejector mechanism including a pivotable handle. Inparticular, the '304 publication describes the blade server as beingconfigured as a field replaceable unit removably receivable in a carrierof a modular computer system, such as a high-density blade serversystem. The blade server is provided with an enclosure and can beprovided with a plurality of processors within the enclosure, which maybe larger than a standard enclosure for a blade server having a singleprocessor. The carrier can be configured to receive such an oversizedblade server enclosure as well as a standard enclosure. The '993publication particularly describes the ejector mechanism, which canpossibly also act as an injection mechanism, as being located at theelongate front face of the blade server and as including an elongatelever extending substantially along the elongate front face. A pivotalmounting for the lever is located toward a first end thereof, and anejection protrusion is also provided at the first end. In a blade serverhaving a greater width than a conventional blade server, the lever andejector mechanism are shown as extending across only the portion of thewidth of the blade server corresponding to the width of a conventionalblade server. Thus, the number of contact surfaces for insertion andejection is not increased when the width of the blade server isincreased, and the distance between contact surfaces is likewise notincreased. What is needed is an arrangement providing additional contactsurfaces for insertion and ejection when the width of an individualblade is increased and for providing an increased distance between suchcontact surfaces in the direction of increased blade width.

U.S. Pat. No. 5,173,845 describes a frontplane structure for use with anumber of parallel printed circuit boards having respective sets of aplurality of electrical connectors mounted to their front edges. Thefrontplane structure includes a multi-layer printed circuit boardmounted to a sheet metal sub-chassis that includes integralinjector/ejector devices which, by means of a cam action, produce areduction in the mechanical effort required to mate the frontplane witheach of the connectors contained on the number of printed circuit boardassemblies installed into a card cage assembly or computer chassis towhich the frontplane is to be connected. A plurality of high-densityprinted circuit connectors are mounted to the multi-layer printedcircuit board for interconnecting with the sets of connectors mounted tothe front edge of the printed circuit board assemblies. What is neededis an arrangement providing a number of contact surfaces for theinsertion and ejection of individual electronic modules without removinga frontally disposed structure from all of the modules.

U.S. Pat. No. 4,995,821 describes a system for latching a plurality ofconnector modules or multimodule units in an array to a panel, with thesystem including opposing parallel assemblies mounted to the panel, eachhaving a plurality of cam levers in associated opposing pairs at eachmodule site. The cam levers are mounted along respective shafts of theassemblies, being adapted to be reciprocally rotatable about theoutwardly from and inwardly toward the array. Each cam lever includes arecess into which a latching projection of a module is receivable uponmodule insertion into the array. When the cam lever is rotated inwardly,the recess urges the module into a fully mated position in itsreceptacle connector. When the cam lever is rotated outwardly, therecess raises the projection, ejecting the module from the receptacleconnector. Several cam levers can be ganged together by means of a pinextending through holes in the cam levers near an end opposite the endat which the cam levers are pivoted, to be rotatable outwardly as aunit, corresponding to several modules ganged as a unit. What is neededis a method for varying the arrangement of cam levers pivotally mountedon individual modules to compensate for dimensional variations among thevarious modules. Furthermore, while U.S. Pat. Nos. 5,173,845 and4,995,821 describe methods for ganging cam levers together with shaftsor pins extending through an end of the levers opposite the end at whichthey are pivotally mounted, what is needed is a method for simplyextending a pivot shaft arrangement to gang such levers together.

U.S. Pat. No. 5,426,567 describes a structure including similarelectronic module packages having guide pins and front actuatedretaining rods for mounting the packages on a mounting panel havingthreaded mounting holes spaced in a regular pattern to accept the guidepins and retaining rods of several module packages. The guide pins andretaining rods are mounted on diagonally opposite corners of themodules. Various arrangements of modules on the mounting panel areallowed by suitable arrangement of the pattern of mounting holes in thepanel. While the retaining rods fasten modules of varying size to thepanel, forces to engage and disengage connector terminals during theinstallation and removal of the modules are not provided by theretaining rods.

SUMMARY OF THE INVENTION

In accordance with one aspect of the invention, apparatus is providedincluding an electronic enclosure, a first lever, and a first pivotshaft. The electronic enclosure has a latching side and a free side,opposite the latching side. The first lever is pivotally mounted to bedisposed along the latching side and to be movable between an openposition and a closed position. The first lever includes a first toothmoving outward from the electronic enclosure and forward along theelectronic enclosure as the first lever is moved from the open positionto the closed position. The first pivot shaft extends between the firstlever and the free side, being attached to the first lever to pivot withthe first lever. The first pivot shaft includes a first outer couplingsurface including an angular positioning element, exposed at the freeside and disposed at a first predetermined angle with respect to thefirst tooth.

The coupling surface including an angular positioning element providesan ability to mount a shaft or a latching plate on the end of the firstpivot shaft so that features of the shaft or latching plate will turnwith the shaft, remaining in a particular alignment with features of thefirst lever, such as the first tooth. The apparatus may additionallyinclude an expansion unit attached to extend outward from the free sideof the electronic enclosure and an outer end crank plate, including aninner coupling surface including an angular positioning element,removably attached to the first pivot shaft to be disposed along thefree side of the electronic enclosure and to pivot with the first lever.The outer end crank plate includes a tooth aligned with the first tooth.

Furthermore, the apparatus may include an intermediate crank platemounted on the first pivot shaft including a tooth outwardly exposedfrom the electronic enclosure in alignment with the first tooth of thefirst lever. Such an intermediate crank plate is disposed between thelatching side and the free side of the electronic enclosure.

The apparatus may additionally include an interlocking mechanismelectrically operated to selectively block pivoting movement of thefirst pivot shaft from the closed position to the open position.

In accordance with another aspect of the invention, electronic apparatusis provided including a cabinet and first and second electronicenclosures. The cabinet includes a first panel having a plurality ofslots extending in a line, spaced apart with a first distance betweenadjacent slots, and a guiding structure associated with each of theslots. The first electronic enclosure includes a latching side, a freeside opposite the latching side, and a first lever, disposed at thelatching side, including a first tooth engaging a first slot within theplurality of slots in the first panel. The first electronic enclosure isdisposed between the first slot in the first panel and a second slot inthe first panel, adjacent the first slot in the first panel and outsidea space adjacent the second slot in the first panel. The secondelectronic enclosure includes a latching side, an opposite side oppositethe latching side, a second lever, disposed at the latching side,including a second tooth, engaging a third slot within the plurality ofslots in the first panel, and a first crank plate, including a thirdtooth, engaging a fourth slot within the plurality of slots in the firstpanel, and a first pivot shaft connecting the second lever and the firstcrank plate to turn together with the second and third teeth alignedwith one another, wherein the second and third teeth move forward alongthe second electronic enclosure and into the third and fourth slotswithin the plurality of slots as the first pivot shaft is moved from anopen position to a closed position.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a fragmentary perspective view of an electronic enclosure,built in accordance with the invention, partly inserted within a cabinettogether with an expansion unit;

FIG. 2 is a fragmentary cross-sectional elevation of the cabinet of FIG.1, with the electronic enclosure of thereof partly inserted therein;

FIG. 3 is a fragmentary perspective view of the electronic enclosure andextension unit of FIG. 1, fully inserted within the cabinet thereof;

FIG. 4 is a perspective view of an upper lever of the electronicenclosure of FIG. 1, showing elements thereof in an explodedrelationship with one another;

FIG. 5 is a longitudinal cross-sectional elevation of an upper pivotshaft built in accordance with the invention within in an electronicenclosure having a standard width;

FIG. 6 is a perspective view of a left end of the upper pivot shaft ofFIG. 5 in an exploded relationship with an upper lever attached theretoand with a right end of an extension shaft attachable thereto;

FIG. 7 is a perspective view of a right end of the upper pivot shaft ofFIG. 5;

FIG. 8 is a longitudinal cross-sectional elevation of an upper pivotshaft built in accordance with the invention within an electronicenclosure of FIGS. 1 and 3;

FIG. 9 is a perspective view of elements in the upper pivot shaft ofFIG. 8 in an exploded relationship with one another;

FIG. 10 a perspective view of the right end of a sleeve within the upperpivot shaft of FIG. 8;

FIG. 11 is a fragmentary cross-sectional elevation of a firstalternative expansion unit, built in accordance with the invention andattached to a free side of an electronic enclosure;

FIG. 12 is a fragmentary cross-sectional elevation of a secondalternative expansion unit, built in accordance with the invention andattached to a latching side of an electronic enclosure;

FIG. 13 is a perspective view of the left end of an extension shaftwithin the expansion unit of FIG. 12 in an exploded relationship with acrank plate therein;

FIG. 14 is a fragmentary perspective view of a cabinet and an electronicenclosure, built in accordance with the invention to include a firstversion of an interlock mechanism; and

FIG. 15 is a fragmentary perspective view of an electronic enclosure,built in accordance with the invention to include a second version of aninterlock mechanism.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a fragmentary perspective view of an electronic enclosure 10built in accordance with the invention, together with an expansion unit12, which are together partly inserted within a cabinet 14. For example,the electronic enclosure 10 includes a computer system configured as ablade server, while the expansion unit 12 includes a number of hard diskdrive units providing additional storage to be used by the blade server.The electronic enclosure 10 and the expansion unit 12 are physicallyattached to one another, and are removed from and installed within thecabinet 14 as a unit.

FIG. 2 is a fragmentary cross-sectional elevation of the cabinet 14,with the electronic enclosure 10 partly inserted therein, showing alower rear portion of the enclosure 10. The enclosure 10 includes anumber of contact terminals 16, extending rearward, in the direction ofarrow 18 to make electrical contact with contact springs 20 withinconnectors 22 of the cabinet 14. For example, the connectors 22 areattached to a circuit board 24 extending along an internal rear surface26 of the cavity 26 provided within the cabinet 14 for receivingelectronic enclosures.

The cabinet 14 includes a lower panel 30 having a number of raisedstructures 32 providing lateral guiding surfaces 34 guiding theelectronic enclosure 10 as it is inserted into the cabinet 14 in therearward direction of arrow 18 and as it is subsequently withdrawn fromthe cabinet 14 opposite the direction of arrow 18. The electronicenclosure 10 includes a pair of downwardly directed edge rails 36sliding in grooves 38 between adjacent raised structures 32. The cabinet14 additionally includes an upper panel 40, having features similar tothe lower panel 30, with upwardly-directed edge rails 42 of theelectronic enclosure 10 sliding along grooves between depressedstructures (not shown) in the upper panel 40.

The electronic enclosure 10 additionally includes an insertion/ejectionmechanism having a lower lever 44 and an upper lever 46. The lower lever44 is pivotally mounted by means of a pivot shaft 48 near a lower frontcorner of a latching side 50, which is, for example, the left side ofthe electronic enclosure 10. The upper lever 46 is pivotally mounted bymeans of a pivot shaft 49 near an upper front corner of the latchingside 50. Each of the levers 44, 46 includes a handle portion 52 and aslot-engaging tooth 54. Before the electronic enclosure 10 can be fullyinserted within the cabinet 14, the levers 44, 46 must be pivoted sothat their handles 52 extend forward, opposite the direction of arrow18, allowing the slot-engaging teeth 54 to be moved into place adjacentslots within the panels 30, 40.

FIG. 3 is a fragmentary perspective view of the electronic enclosure 10with the expansion unit 12, as fully inserted within the cabinet 14, tobe held in place by the slot-engaging tooth 54 of the lower lever 46extending within a slot 56 of the lower panel 30 and by theslot-engaging tooth 54 of the upper lever 46 extending within a slot 58of the upper panel 40. The electronic enclosure 10 is moved from thepartially inserted position of FIG. 1 to the fully inserted position ofFIG. 3 by pivoting the handle 52 of the lower lever 44 upward, in thedirection indicated by arrow 60, and by simultaneously pivoting thehandle 52 of the upper lever 46 downward, in the direction of arrow 62.During this pivoting motion, the slot-engaging tooth 58 of each of thelevers enters an adjacent slot 56, 58 and, engaging a front edge 64 ofthe slot 56, 58 pushes against the edge 64 to move the electronicenclosure 10 rearward, in the direction of arrow 18 as the contactterminals 16 are moved in engagement with the contact springs 20 (shownin FIG. 2).

The cabinet 14 is configured to accept a number of conventionalelectronic enclosures (not shown), each of which includes a latchingside, having lower and upper levers similar to levers 44, 46, and a freeside, opposite the latching side, that does not include such levers.Thus, adjacent slots 58 within the lower panel 30 and the upper panel 40are spaced apart through a distance allowing such conventionalelectronic enclosures (not shown) to be inserted along guiding surfaces34 with teeth of the levers extending within the slots 58.

FIG. 4 is an exploded view of the upper lever 46, which includes alatching member 66 pivotally mounted on the handle portion 52 by a pin68, together with a latching spring 70 having a cantilever tab 72applying a torque in the direction of arrow 74 to the latching member66, so that a tooth 76 of the latching member 66 is held within a notch78 of a latching bracket 80 when the upper lever 46 is held in theclosed position of FIG. 3. The lower lever 46 includes a similararrangement, with a tooth 82 of a latching member 84 being held in anotch of a second latching bracket 86. In this way, the lower lever 44and the upper lever 46 form a structure holding the electronic enclosure10 in place within the cabinet 14 after it is fully inserted therein.

When the electronic enclosure 10 is to be removed from the cabinet 14,the handle portions 52 of the lower lever 44 and the upper lever 46 aregrasped to be moved outward, opposite the direction of arrows 60, 62.The latching members 66, 84 each have a curved surface 88 extendingalong inner surfaces of the handle portions 52, so that, as the levers44, 46 are gripped to be moved outward, the latching portions 66, 84 arepivoted in the directions of arrows 89, releasing the teeth 76, 82 ofthe latching members 66, 84 from the notches within the latchingbrackets 80, 86, allowing rotation of the levers 44, 46 opposite thedirection of arrows 60, 62. This rotation of the levers 44, 46 causesthe teeth 54 of the levers 44, 46 to slide in contact with the rearedges 90 of the associated slots 56, 58, ejecting the electronicenclosure outward, opposite the direction of arrow 18, through a shortdistance, disengaging the contact terminals 16 from the contact springs20.

The guiding structures 32 and slots 56, 58 of the cabinet 14 are spacedto allow the cabinet 14 to be filled with electronic enclosures eachhaving a standard width, with the teeth 54 of the levers 44, 46 ofadjacent enclosures fitting within adjacent slots 56, 58. The cabinet 14additionally accepts electronic enclosures, such as the electronicenclosure 10, having a width equal to a multiple of the standard widths.

In accordance with a first version of the invention, such an enclosure10 includes a lower crank plate 92, connected by the lower pivot shaft48 to turn with the lower lever 44 and an upper crank plate 94,connected by the upper pivot shaft 49 to turn with the upper lever 46.The lower crank plate 94 includes a tooth 96 aligned with the tooth 54of the lower lever 44. As the lower lever 44 is rotated in the directionof arrow 60 into the closed position of FIG. 2, the tooth 96 engages aslot 98 in the lower panel 30 adjacent the slot 56, pulling theenclosure 10 inward, in the direction of arrow 18. Similarly, the uppercrank plate 94 has a tooth 96 aligned with the tooth 54 of the upperlever 56, connected to the upper pivot shaft 49, which engages a slot(not shown) in the upper panel 40 to pull the enclosure 10 inward as theupper lever 46 is pivoted in the direction of arrow 62. This arrangementspreads the application of insertion forces, acting in the direction ofarrow 18, along the width of the enclosure 10, in the direction of arrow100, reducing a tendency of the enclosure 10 to twist and drag along theguiding surfaces 34 as it is inserted, in opposition to forces acting oncontact terminals 16 extending across the width of the enclosure 10.

Similarly, as the levers 44, 46 are rotated out of the closed positionof FIG. 3, opposite the directions of arrows 60, 62, respectively, themovement of the teeth 96 within slots in the panels 30, 40 provideforces acting on the enclosure 10 opposite the direction of arrow 18,aiding in the ejection of the enclosure 10 without substantial twistingand dragging along the guiding surfaces 34 as the contact terminals 16are pulled away from the contact springs 20.

In accordance with a second version of the invention, the lower pivotshaft 48 is provided with means for attaching a lower end crank plate102 including a tooth (not shown) additionally aligned with the tooth 54of the lower lever 44. The upper pivot shaft 49 is similarly providedwith means for attaching an upper end crank plate 104 having a tooth 106additionally aligned with the tooth 54 of the upper lever 44. As thelower lever 44 is rotated in the direction of arrow 60 into the closedposition of FIG. 2, the tooth of the lower end crank plate 102 engages aslot 108 in the lower panel 30, pulling the enclosure 10 inward, in thedirection of arrow 18. Similarly, the tooth 96 engages a slot (notshown) in the upper panel 40 to pull the enclosure 10 inward as theupper lever 46 is pivoted in the direction of arrow 62. This arrangementfurther spreads the application of insertion forces, acting in thedirection of arrow 18, along the width of the enclosure 10, in thedirection of arrow 100, reducing a tendency of the enclosure 10 to twistand drag along the guiding surfaces 34 as it is inserted, in oppositionto forces acting on contact terminals 16 extending across the width ofthe expansion unit 12, as well as across the width of the enclosure 10.

Similarly, as the levers 44, 46 are rotated out of the closed positionof FIG. 3, opposite the directions of arrows 60, 62, respectively, themovement of the teeth of end crank plates 102, 104 within slots in thepanels 30, 40 provide forces acting on the enclosure 10 opposite thedirection of arrow 18, aiding in the ejection of the enclosure 10without substantial twisting and dragging along the guiding surfaces 34as the contact terminals 16 are pulled away from the contact springs 20.

An upper pivot shaft built in accordance with the invention to be heldwithin an electronic enclosure having a standard width, corresponding tothe distance between adjacent slots 56 in the lower panel 30 and betweenadjacent slots 58 in the upper panel 40, will now be discussed withreference to FIGS. 5-7. Features identical or similar to the featurespreviously discussed with reference to FIGS. 1-4 are accorded likereference numbers.

FIG. 5 is a fragmentary cross-sectional elevation of the upper pivotshaft 110 within such a standard-width electronic enclosure 112, whichincludes upwardly directed rails 42 for guidance into a position withinthe cabinet 14. The electronic enclosure 112 is shown as installedwithin the cabinet 14, with the tooth 54 of the lever 46 engaging a slot113, among the slots 58 of the upper panel 40. The enclosure 112 alsoincludes a pair of holes 114, aligned with one another, in which theupper pivot shaft 110 is held. The upper lever 46 is attached to theupper pivot shaft 110 to extend downward along a latching side 116 ofthe enclosure 112. In the example of FIG. 5, the upper pivot shaft 110is pivotally attached to be removed and installed with the latching side116, being held thereto by a snap-on retaining ring 118. The electronicenclosure 112 additionally includes a free side 119, opposite thelatching side 116, without a mechanism for insertion and injection, suchas the upper lever 46. As an example of a standard-width enclosure, theelectronic enclosure 112 occupies an area between the slot 113 and asecond slot 120 adjacent this slot 58 but beyond the free side 119, withthe electronic enclosure 112 being spaced away from this second slot 120so that another electronic enclosure may be placed adjacent theenclosure 112 with the lever 46 of the other electronic enclosureengaging the slot 120.

FIG. 6 is a perspective view of a left end 121 of the upper pivot shaft110 in an exploded relationship with the upper lever 46, andadditionally with a right end 122 of an upper left extension shaft 124,optionally attached as a part of an expansion unit extending from thelatching side of an electronic enclosure. For example, the upper pivotshaft 110 is attached to the upper lever 56 with an end stud 126 of theshaft 110 extending within a hole 128 in the upper lever 56 byprojection welding a ring shaped projection 130 on the shaft 110 to anadjacent surface of the upper lever 56. The left end 121 of the shaft110 also includes a groove 132 for accepting the retaining ring 118.

FIG. 7 is a perspective view of a right end 134 of the upper pivot shaft110, showing a notch 136 used, for example, to align the end upper crankplate 104, discussed above in reference to FIG. 3, so that its tooth 106is in alignment with the tooth 54 of the upper lever 46. The right end134 of the shaft 110 additionally includes an alignment hole 138 and athreaded hole 140, which are used, for example, for the attachment ofthe end upper crank plate 104. Thus, the right end 134 of the shaft 110forms a coupling surface including an angular positioning element in theform of the notch 136, which is used to angularly position a shaft orplate attached to the shaft end 134 with respect to other features ofthe shaft.

The upper pivot shaft 49, previously described in reference to FIGS.1-4, used within the electronic enclosure 10, which has a width equal totwice the standard width, will now be described with additionalreferences being made to FIGS. 8-10.

FIG. 8 is a longitudinal cross-sectional elevation of the upper pivotshaft 49, within the electronic enclosure 10. The upper pivot shaft 49includes a first section 146, which is preferably identical to the shaft110 used, as described above in reference to FIGS. 5-7, in an electronicenclosure 112. The upper pivot shaft 49 additionally includes a secondsection 148 including a core pin 150 and a sleeve 152. The core pin 150includes a threaded portion 153, engaging a threaded hole 154 within thefirst section 146, and a cylindrical alignment portion 156 engaging analignment hole 158 within the first section 146.

FIG. 9 is a perspective view of the central portion 160 of the upperpivot shaft 49, showing the right end 162 of the first section 146 in anexploded relationship with the upper crank plate 94 and with the leftend 164 of the sleeve 152. As the core pin 150 is inserted within thehole 166 of the sleeve 152, its cylindrical alignment portion 156 isinserted to extend through a hole 168 within the upper crank plate 94into the hole 158 within the first section 146.

FIG. 10 is a perspective view of a right end portion 170 of the upperpivot shaft 49, in which the core pin 150 is seen as including a slot172 by which it is turned, with its threaded portion 153 in engagementwith the threaded hole 154 within the first section 146, to clamp theupper crank plate 94 in place between the end face 174 of the sleeve 152and the end face 176 of the first section 146.

The upper crank plate 94 includes a key tab 178 extending into a notch180 within the first section 146 to ensure that the tooth 96 of theupper crank plate 94 remains in alignment with the tooth 54 of the upperlever 46 as the upper pivot shaft 49 is rotated. Thus, the upper crankplate is understood to have a coupling including an angular positioningelement in the form of the tab 178, engaging the angular positioningelement of the coupling at the first section 146, in the form of thenotch 180. The upper crank plate 94 additionally includes a pair ofslots 182, forming angular positioning elements, in which tabs 184,forming additional angular positioning elements, extending from thesleeve 152 are held. The sleeve 152 includes a notch 183, forminganother angular positioning element, which engages a key tab 184 of theupper end crank plate 104, which is held in place on the right end face186 of the sleeve 152 by means of a screw 188 extending into a threadedhole 190 and an alignment hole 192 of the core pin 150. Thus, while thecore pin 150 is allowed to rotate in threaded engagement with the firstsection 146, as required to clamp the upper crank plate 94 in place,alignment features of the first section 146, the upper crank plate 94,the sleeve 152, and the end upper crank plate 104, hold the tooth 106 ofthe upper end crank plate 104 in alignment with the tooth 96 of thecrank plate 94 and with the tooth 54 of the upper lever 52. Preferably,the end crank plate 104 and the crank plate 94 are identical parts.

If the electronic enclosure 10 is installed without the expansion unit12, the end crank plate 104 and the screw 188 are preferably omitted, sothat a space is provided within the cabinet 14 for another electronicenclosure to be installed immediately adjacent the enclosure 10, with alever 46 having a tooth 54 engaging the slot 58 within the upper panel40 that would otherwise be engaged by the tooth 106 of the end crankplate 104. Preferably, both the end crank plate 104 and the crank plate94, being identical, include an central portion 194, offset to the left,in the direction of arrow 196, allowing the right end 198 of the upperpivot shaft 49 to be similarly offset from the tooth 106 of the endcrank plate 104, so that an adjacently installed electronic enclosurewill be spaced away from this shaft 49. However, the alignment andattachment features at the right end of the upper pivot shaft 49 remainavailable to provide for installation of an end crank plate 104 if anexpansion unit 12 is added at to the free end 119 of the electronicenclosure at a later time.

FIG. 11 is a fragmentary cross-sectional elevation of a firstalternative expansion unit 210, attached to the free side 211 of theelectronic enclosure 10. The first alternative expansion unit 210 has acover 212 that includes a hole 214 in which an expansion shaft 216 isrotatably mounted. The expansion shaft 216 includes a sleeve 218 and acore pin 220, which are preferably is identical to the sleeve 152 andcore pin 150, respectively, described above in reference to FIGS. 8-10.The core pin 220 replaces the screw 188 of FIG. 8, holding the upper endcrank plate 94 in place and providing a right end 222 having featuresfor mounting another upper end crank plate, either by means of anotherscrew 188 or by means of another expansion shaft 216, in the event thatan additional expansion unit is attached to extend farther to the right,opposite the direction of arrow 196.

An insertion and ejection mechanism built in accordance with theinvention for use with an expansion unit attached to the latching sideof an electronic enclosure will now be discussed, with particularreference being made to FIGS. 6, 12, and 13.

FIG. 12 is a fragmentary cross-sectional elevation of a secondalternative expansion unit 230, attached to the latching side 50 of theelectronic enclosure 10 to extend outward therefrom in the direction ofarrow. The second alternative expansion unit 230 has a cover 232including a hole 234 in which the upper left extension shaft 124 isattached.

FIG. 13 is a perspective view of the outer (left) end 240 of the upperleft extension shaft 124 in an exploded relationship with an alternativecrank plate 242, which is attached to the outer end 240 by projectionwelding a ring projection extending outward from the end 240 to anadjacent surface of the alternative crank plate 242, with a stud portion244 of the shaft 124 extending within a hole 246 within the crank plate242.

As shown in FIG. 6, the right end 122 of the upper left extension shaft124 includes a pair of tabs 248, forming angular positioning element,that extend into slots 250 within the upper lever 46, which also formangular positioning elements. The extension shaft 236 is fastened to thecover 232 by means of a snap on retaining clip 238. When the secondalternative expansion unit 230 is fastened to the latching end 50 of theelectronic enclosure 10 with a stud portion 252 of the extension shaft236 being driven into an alignment hole 254 of the upper pivot shaft110, the alternative crank plate 242 is held in an orientation allowingthe tabs 248 to enter the slots 250 with the tooth 252 of thealternative crank plate 242 in alignment with the tooth 54 of the upperlever 46. The alternative crank plate 242 additionally includes a pairof slots 256 aligned with the slots 250 of the upper lever 46 to providefor the installation of yet another expansion unit 230 to extend furtheroutward in the direction of arrow 231.

While the configurations of upper pivot shafts and associated elementspivoted with the upper lever 46 have been explained in particular detailin reference to FIGS. 5-13, it is further understood that, in accordancewith the invention, similar variations are additionally made to lowerpivot shafts pivoted with the lower lever 44.

The cabinet 14 is of a flexible design, providing a number of spaces forsimultaneously holding various types of electronic enclosures, such asthe electronic enclosures 10, 112, both with and without expansion units12, 232. The term “electronic enclosure” is understood to refer toeither an electronic enclosure extending between a latching side and afree side, retaining a capability to have an expansion unit added toeither or both the latching side and/or the free side, or an electronicenclosure including an expansion unit.

While the preceding discussion has described methods for attachingelements to one another so that tabs are located within notches orkeyways to assure proper alignment between the slot-engaging teeth ofthe levers and cranks, it is understood that such elements may beomitted, with the various parts being manually aligned with one anotheras they are assembled and connected with mating threaded surfaces.

FIG. 14 is a fragmentary perspective view of a cabinet 260 and anelectronic enclosure 262 built in accordance with a version of theinvention to include a first version of an electrically operatedinterlocking mechanism, which selectively prevents the insertion orremoval of the electronic enclosure 262 from the cabinet 260.

The cabinet 260 is generally like the cabinet 14, as described above inreference to FIGS. 1-4, except that the cabinet 260 includes means fordetermining when electronic enclosures may be inserted and removed and anumber of contact structures 264 upon which a voltage is impressed upondetermining that a time has been reached to allow the insertion andremoval of electronic enclosures. In one implementation, a local cabinetmanagement device controls the electronic locking mechanism. The logicfor locking or unlocking may be present within the local cabinetmanagement device or within a remote management device or system. Such adetermination may be based on security concerns, with the insertion andremoval of enclosures being allowed only during certain time periods orin response to providing a security key or password. Alternately, such adetermination may be based on a determination that electrical power hasbeen turned on or off in certain systems or blade servers, or thatcertain processes are not currently occurring, so that an electricalenclosure may be inserted or removed without causing damage to circuitsor a loss of stored data.

The electronic enclosure 262 is generally like the electronic enclosure10, as additionally described above in reference to FIGS. 1-4, exceptthat an interlock mechanism, operating in response to the voltageapplied to the contact structures 264 of the cabinet 260, is provided toselectively block the rotation of the upper pivot shaft 266 and of thelower pivot shaft 268 as required for the insertion or removal of theenclosure 264. For example, the electronic enclosure 262 is providedwith a contact structure 270 making electrical contact with anunderlying contact structure 264 of the cabinet 260, and with a solenoid272 connected to the contact structure 264 by wires 274. The plunger 276of the solenoid 272 is pulled to the rear, in the direction of arrow 278when an electrical current is directed through the solenoid 272 by thewires 274, acting against a force supplied by a compression spring 280.The solenoid plunger 276 is connected by a link 282 to an upperinterlocking crank 284, which is pivotally mounted within the enclosure262 by attachment to a pivoting interlocking shaft 286. On the upperpivot shaft 286, an upper crank plate 288 includes a pawl portion 290extending rearward above the upper interlocking crank 284 with theinterlocking crank 284 held in its forward position by the compressionspring 280, preventing rotation of the upper pivot shaft 286 in thedirection of arrow 292, so that the upper crank plate is held in itslocked position. Preferably, a lower interlocking crank 294 isadditionally attached to the pivoting interlocking shaft 286 to extendabove a pawl portion 296 of a lower crank plate 298 attached to thelower pivot shaft 268 when electrical power is not applied to thesolenoid 272, preventing movement of the lower pivot shaft 268 from thelocked position in which it is shown in the direction of arrow 300.Thus, the electronic enclosure 262 is held in the cabinet 260 with thepivot shafts 266 and 268 in their closed positions, as shown, since theupper lever 302 cannot be rotated in the direction of arrow 292, andadditionally since the lower lever 304 cannot be rotated in thedirection of arrow 300, until a voltage is applied to the contactstructures 264 to operate the solenoid 272.

When the electronic enclosure 262 is being inserted into the cabinet260, the levers 302, 304 must be held in their open positions, as shownin FIG. 1, before they can be moved into their closed positions. If anattempt is made to install the enclosure 262 with these levers in theirclosed positions, the teeth 306 of the levers 302, 304 and cam plates290, 298 will prevent full insertion of the enclosure 262 into thecabinet 260. Preferably, the upper pivot shaft 266 is provided with atorque spring 308 exerting a torque opposite the direction of arrow 292,so that this shaft is held in its closed position with the electronicenclosure 262 removed from the cabinet 260, with this spring beingstrong enough to overcome the compression spring 280 as the pawl portion290 of the upper crank plate 288 is rotated past the upper interlocklever 284 opposite the direction of arrow 292. Additionally, the lowerpivot shaft 262 is preferably provided with a similar torque spring 310,so that this shaft 262 is also held in its closed position with theenclosure 262 removed from the cabinet 260. The contact structure 264 isthen arranged to apply a voltage operating the solenoid 272 through thecontact structure 270 before the enclosure 262 is fully installed,allowing the levers 302, 304 to be moved into their open position duringthe installation of the enclosure 262 at any time during which thisvoltage is present.

Thus, the interlocking mechanism of FIG. 14 selectively blocks thepivoting movement of the upper pivot shaft 266 and of the lower pivotshaft 268 from closed positions to open positions. The interlockingmechanism includes a first pawl surface of pawl portion 290 attached tothe upper pivot shaft 266 and a second pawl surface of the pawl portion296 attached to the lower pivot shaft 268. A first interlockingstructure, in the form of interlocking crank 290, is held in a positionblocking movement of the first pawl surface by the compression spring280. Additionally, a second interlocking structure, in the form ofinterlocking crank 294, is held in a position blocking movement of thesecond pawl surface by the compression spring 280. The solenoid 272moves both the first and second interlocking structures out of thesepositions blocking movements of pawl surfaces.

Electrical power may be placed on all of the contact structures 264within the cabinet 260 so that any electronic enclosure 262 held withinthe cabinet 260 can be removed. In another version of the invention,electrical power is applied to one or more individual contact structures264 so that only a certain electronic enclosure 262, or a certain groupof electronic enclosures 262, can be removed. In this way, the abilityto release individual electronic enclosures 262 can be controlled from aremote location.

Optionally, a release lever 312 is attached to the pivoting interlockingshaft 286 to provide for the manual rotation of the shaft 286 in theevent of a power failure, with the lever 312 being pushed with a rodthrough a hole 314 in the electronic enclosure 10.

FIG. 15 is a fragmentary perspective view of an electronic enclosure 320built in accordance with another version of the invention to include asecond version of an interlocking mechanism, which selectively preventsthe removal of the electronic enclosure 320 from the cabinet 14,discussed above in reference to FIGS. 1-4. The electronic enclosure isgenerally like the electronic enclosure 10, as additionally describedabove in reference to FIGS. 1-4, except that an interlock mechanismincluding a solenoid 322, operating in response to signal from a circuit324 within the enclosure 320, is provided to selectively block therotation of an upper pivot shaft 326, as required for the removal of theenclosure 320 from the cabinet 14. For example, the circuit 324 mayprovide a voltage to operate the solenoid 322 during times in which theremoval of the enclosure 320 from the cabinet 14 may cause damage tocomponents or a loss of stored data. A security feature may beimplemented by operating the solenoid to block removal of the enclosure320 until a certain time of day has been reached or until apredetermined password has been provided as an input to the managementdevice or system.

The plunger 326 of the solenoid 322 is pulled to the rear, in thedirection of arrow 328, when a voltage is applied to the solenoid 322.Otherwise, the plunger 326 is held forward, opposite the direction ofarrow 328 by a compression spring 330. The plunger 326 is connected by alink 332 to an interlocking lever 336, which is pivotally mounted on abracket 338. When the voltage is not applied to the solenoid 322, theupper surface 340 of the interlocking lever 336 is held away from a pawlportion 342 extending rearward as a part of the upper crank plate 344,allowing rotation of the upper pivot shaft 338 in the direction of arrow346 for removal of the enclosure 320 from the cabinet 14. On the otherhand, when the voltage is applied to the solenoid 322, the upper surface340 of the interlocking lever 336 is moved under the pawl portion 342,preventing rotation of the upper pivot shaft 338 for removal of theenclosure 320 from the cabinet 14.

Thus, the interlocking mechanism of FIG. 14 selectively blocks thepivoting movement of the upper pivot shaft 326 from a closed position toan open position. This interlocking mechanism includes a pawl surface ofpawl portion 342 and an interlocking structure, in the form of theinterlocking lever 336 that is moved into position to block movement ofthe pawl portion by the solenoid 322, and that is otherwise held awayfrom the pawl portion by the compression spring 330.

In accordance with the invention, an interlocking mechanism can beapplied to selectively prevent pivoting movement of both the upper andlower pivot shafts, in the manner of FIG. 14, or to selectively preventsuch movement of only one of these shafts, in the manner of FIG. 15. Ineither such interlocking mechanism, the prevention of such movement mayoccur in response to applying a voltage to a solenoid, or in response tonot applying a voltage to a solenoid. While FIGS. 14 and 15 show pawlsurfaces being formed as portions of crank plates, it is understood thata lever including a pawl surface can readily be added to a shaft, suchas the upper shaft 110 of FIG. 5, not including a crank plate.

While the invention has been described in its preferred forms orembodiments with some degree of particularity, it is understood thatthis description has been given only by way of example, and that manyvariations in the arrangement of parts can be made without departingfrom the scope and spirit of the invention, as defined in the appendedclaims.

1. The Apparatus comprising: an electronic enclosure having a latchingside and a free side, opposite the latching side; a first lever,pivotally mounted to be disposed along the latching side and to bemovable between an open position and a closed position, wherein thefirst lever includes a first tooth moving outward from the electronicenclosure and forward along the electronic enclosure as the first leveris moved from the open position to the closed position; and a firstpivot shaft extending between the first lever and the free side, whereinthe first pivot shaft is attached to the first lever to pivot with thefirst lever as the first lever is moved between the open position andthe closed position; and wherein the first pivot shaft includes a firstouter coupling surface including an angular positioning element, exposedat the free side and disposed at a first predetermined angle withrespect to the first tooth, an expansion unit attached to extend outwardfrom the free side, and an outer end crank plate, including an innercoupling surface including an angular positioning element, removablyattached to the first pivot shaft to be disposed along the free side ofthe enclosure and to pivot with the first lever as the first lever ismoved between the open position and the closed position, wherein theouter end includes a first outer tooth aligned with the first tooth ofthe first lever by engagement between the inner coupling surfaceincluding an angular positioning element of the outer end crank plateand the first outer coupling surface including an angular positioningelement of the first pivot shaft.
 2. The apparatus of claim 1, whereinthe first pivot shaft includes a threaded hole extending from a surfaceof the first pivot shaft at the free side of the electronic enclosure,and the outer end crank plate is removably attached to the first pivotshaft by means of a screw engaging the threaded hole.
 3. The apparatusof claim 1, wherein the expansion unit includes: a cover having anextension shaft mounting hole; and an extension shaft mounted within theextension shaft mounting hole to pivot with the first pivot shaft havingan outer coupling surface including an angular positioning element,exposed at a side of the expansion unit opposite the electronicenclosure and disposed at a first predetermined angle from the firsttooth.
 4. The apparatus of claim 3, wherein the outer end crank plateadditionally includes an outwardly directed outer coupling surfaceincluding an angular positioning element disposed at a firstpredetermined angle with respect to the inner coupling surface includingan angular positioning element of the outer end crank plate, and theextension shaft additionally includes an inner coupling surfaceincluding an angular positioning element engaging the outer couplingsurface including an angular positioning element of the outer end crankplate to dispose the outer coupling surface including an angularpositioning element of the extension shaft at the first predeterminedangle from the first tooth.
 5. The apparatus of claim 4, wherein thefirst pivot shaft includes a threaded hole extending from a surface ofthe first pivot shaft at the free side of the electronic enclosure, andthe extension shaft includes a sleeve including the inner and outercoupling surfaces including angular positioning elements of theextension shaft, and a core pin, extending within the sleeve, having athreaded end engaging the threaded hole of the first pivot shaft and athreaded hole extending from an outer end of the core pin.
 6. TheApparatus comprising: an electronic enclosure having a latching side anda free side, opposite the latching side; a first lever, pivotallymounted to be disposed along the latching side and to be movable betweenan open position and a closed position, wherein the first lever includesa first tooth moving outward from the electronic enclosure and forwardalong the electronic enclosure as the first lever is moved from the openposition to the closed position; and a first pivot shaft extendingbetween the first lever and the free side, wherein the first pivot shaftis attached to the first lever to pivot with the first lever as thefirst lever is moved between the open position and the closed position;and wherein the first pivot shaft includes a first outer couplingsurface including an angular positioning element, exposed at the freeside and disposed at a first predetermined angle with respect to thefirst tooth, wherein the first lever and the first pivot shaft form afirst pivoting structure including a second outer coupling surfaceincluding an angular positioning element, exposed at the latching sideand disposed at a second predetermined angle with respect to the firsttooth.
 7. The apparatus of claim 6, additionally comprising an expansionunit attached to extend outward from the latching side, wherein theexpansion unit includes: a cover having an extension shaft mountinghole, an extension shaft mounted within the extension shaft mountinghole to pivot with the first pivot shaft, having an inner couplingsurface including an angular positioning element engaging the secondouter coupling surface including an angular positioning element of thefirst pivoting structure, and an outer end crank plate, attached topivot with the extension shaft, having an outer tooth aligned with thefirst tooth of the first lever by engagement between the inner couplingsurface including an angular positioning element of the extension shaftand the outer coupling surface including an angular positioning elementof the first pivoting structure.
 8. The apparatus of claim 6, whereinthe extension shaft and the outer end crank plate form a second pivotingstructure including a third outer coupling surface including an angularpositioning element, exposed at a side of the expansion unit oppositethe electronic enclosure, and disposed at the second predetermined anglewith respect to the first tooth.
 9. Apparatus comprising: an electronicenclosure having a latching side and a free side, opposite the latchingside; a first lever, pivotally mounted to be disposed along the latchingside and to be movable between an open position and a closed position,wherein the first lever includes a first tooth moving outward from theelectronic enclosure and forward along the electronic enclosure as thefirst lever is moved from the open position to the closed position; anda first pivot shaft extending between the first lever and the free side,wherein the first pivot shaft is attached to the first lever to pivotwith the first lever as the first lever is moved between the openposition and the closed position; and wherein the first pivot shaftincludes a first outer coupling surface including an angular positioningelement, exposed at the free side and disposed at a first predeterminedangle with respect to the first tooth, and an intermediate crank platemounted on the first pivot shaft between the latching side and the freeside to pivot with the first lever as the first lever is moved betweenthe open position and the closed position, including a second toothoutwardly exposed from the electronic enclosure in alignment with thefirst tooth of the first lever.
 10. The apparatus of claim 9, whereinthe first pivot shaft includes a first section, extending between thefirst lever and the intermediate crank plate, having a firstintermediate coupling surface including an angular positioning elementand a second section, extending between the intermediate crank plate andthe free side of the electronic enclosure, having a second intermediatecoupling surface including an angular positioning element, and theintermediate crank plate includes a third intermediate coupling surfaceincluding an angular positioning element, engaging the firstintermediate coupling surface including an angular positioning elementto hold the second tooth in alignment with the first tooth and a fourthintermediate coupling surface including an angular positioning elementengaging the second intermediate coupling surface including an angularpositioning element to hold the first outer coupling surface includingan angular positioning element to be disposed at the first predeterminedangle with respect to the first tooth.
 11. The apparatus of claim 10,wherein the first section of the first pivot shaft includes a threadedhole extending from an end surface of the first pivot shaft adjacent theintermediate crank plate, and the second section of the first pivotshaft includes a sleeve including the second intermediate couplingsurface including an angular positioning element and the first outercoupling surface including an angular positioning element, and a corepin, extending within the sleeve, having a threaded end, engaging thethreaded hole of the first section, and a threaded hole extending at thefree side of the electronic enclosure.
 12. Apparatus comprising: anelectronic enclosure having a latching side and a free side, oppositethe latching side; a first lever, pivotally mounted to be disposed alongthe latching side and to be movable between an open position and aclosed position, wherein the first lever includes a first tooth movingoutward from the electronic enclosure and forward along the electronicenclosure as the first lever is moved from the open position to theclosed position; a first pivot shaft extending between the first leverand the free side, wherein the first pivot shaft is attached to thefirst lever to pivot with the first lever as the first lever is movedbetween the open position and the closed position; and wherein the firstpivot shaft includes a first outer coupling surface including an angularpositioning element, exposed at the free side and disposed at a firstpredetermined angle with respect to the first tooth, and an interlockingmechanism electrically operated to selectively block pivoting movementof the first pivot shaft from the closed position to the open position.13. The apparatus of claim 12, additionally comprising a pawl surfaceattached to the first pivot shaft, wherein the interlocking mechanismincludes an interlocking structure movably mounted adjacent the pawlsurface, a spring holding the interlocking structure in a positionblocking movement of the pawl surface, and a solenoid moving theinterlocking structure away from the pawl surface to allow movement ofthe pawl surface.
 14. The apparatus of claim 13, wherein theinterlocking mechanism additionally includes a contact structureextending outward from the electronic enclosure to provide electricalpower for the solenoid.
 15. The apparatus of claim 12, additionallycomprising a pawl surface attached to the first pivot shaft, wherein theinterlocking mechanism includes an interlocking structure movablymounted adjacent the pawl surface, a solenoid holding the interlockingstructure in a position blocking movement of the pawl surface, and aspring moving the interlocking structure away from the pawl surface toallow movement of the pawl surface.
 16. The apparatus of claim 13,wherein the interlocking mechanism additionally includes a first contactstructure extending outward from the second electronic enclosure toprovide electrical power for the solenoid.
 17. The apparatus of claim12, wherein the second electronic enclosure additionally comprises apawl surface attached to the first pivot shaft, and the interlockingmechanism includes an interlocking structure movably mounted adjacentthe pawl surface, a solenoid holding the interlocking structure in aposition blocking movement of the pawl surface, and a spring moving theinterlocking structure away from the pawl surface to allow movement ofthe pawl surface.
 18. Apparatus comprising: an electronic enclosurehaving a latching side and a free side, opposite the latching side; afirst lever, pivotally mounted to be disposed along the latching sideand to be movable between an open position and a closed position,wherein the first lever includes a first tooth moving outward from theelectronic enclosure and forward along the electronic enclosure as thefirst lever is moved from the open position to the closed position; anda first pivot shaft extending between the first lever and the free side,wherein the first pivot shaft is attached to the first lever to pivotwith the first lever; and wherein the first pivot shaft includes a firstouter coupling surface including an angular positioning element, exposedat the free side and disposed at a first predetermined angle withrespect to the first tooth wherein the first pivot shaft extends withinthe electronic enclosure adjacent an upper front edge of the electronicenclosure, and wherein the first tooth moves upward from the electronicenclosure and forward along the electronic enclosure as the first leveris moved from the open position to the closed position; and a secondlever pivotally mounted to be disposed along the latching side, toextend within the electronic enclosure, adjacent a lower front edge ofthe electronic enclosure, and to be movable between an open position anda closed position, wherein the second lever includes a second toothmoving downward from the electronic enclosure and forward along theelectronic enclosure as the second lever is moved from the open positionto the closed position, and a second pivot shaft extending between thesecond lever and the free side, wherein the second pivot shaft isattached to the second lever to pivot with the second lever; and whereinthe second pivot shaft includes a first outer coupling surface includingan angular positioning element, exposed at the free side and disposed ata first predetermined angle with respect to the second tooth.
 19. Theapparatus of claim 18, additionally comprising an interlocking mechanismelectrically operated to selectively block pivoting movement of thefirst pivot shaft from its closed position to its open position and toselectively block pivoting movement of the second pivot shaft from itsclosed position to its open position.
 20. The apparatus of claim 19,additionally comprising a first pawl surface is attached to the firstpivot shaft and a second pawl surface is attached to the second pivotshaft, wherein the interlocking mechanism includes a first interlockingstructure movably mounted adjacent the first pawl surface, a secondinterlocking structure movably mounted adjacent the second pawl surface,a spring holding the interlocking structure in a position blockingmovement of the first and second pawl surfaces, and a solenoid movingthe first and second interlocking structures away from the first andsecond pawl surfaces to allow movement of the first and second pawlsurfaces.
 21. The apparatus of claim 20, wherein the interlockingmechanism additionally includes a contact structure extending outwardfrom the electronic enclosure to provide electrical power for thesolenoid.
 22. The apparatus of claim 19, additionally comprising a firstpawl surface is attached to the first pivot shaft and a second pawlsurface is attached to the second pivot shaft, wherein the interlockingmechanism includes a first interlocking structure movably mountedadjacent the first pawl surface, a second interlocking structure movablymounted adjacent the second pawl surface, a solenoid holding theinterlocking structure in a position blocking movement of the first andsecond pawl surfaces, and a spring holding the first and secondinterlocking structures away from the first and second pawl surfaces toallow movement of the first and second pawl surfaces.